Canada announced here on Tuesday its latest set of regulations on cars and light trucks to reduce greenhouse gas (GHG) emissions as the UN climate talks entered its second day in Doha, Qatar.

The proposed regulations - expected to be finalized in 2013 - would require cars with model years 2017 to 2025 to cut on-road emissions by an average of 5 percent every year.

Light trucks, with model years 2017 to 2021, will be required to achieve an average of 3.5 percent reduction in annual GHG emissions, and a 5-percent cut for model years 2022 to 2025.

"Compared to 2008 models, vehicles rolling off the line in 2025 will produce almost 50 percent fewer greenhouse gas emissions and consume up to 50 percent less fuel," said Environment Minister Peter Kent while announcing the newly proposed regulations at a car dealership.

Regulating the transportation sector, which accounts for about 24 percent of Canada's GHG emissions, is part of the government's sector-by-sector approach that has already covered electricity and will eventually apply to the oil and gas sector, Kent said.

However, the strategy has come under fire from critics for not being enough to meet Canada's 2020 target of reducing its GHG emissions by 17 percent from the 2005 levels.

"The sector-by-sector approach is the slowest, weakest and most costly way to reduce greenhouse gas emissions," said John Bennett, executive director of Sierra Club Canada, an Ottawa-based national environmental group.

Canada signed the Kyoto Protocol in 1997, and ratified it in the parliament in 2002, committing itself to the target of reducing GHG emissions to an average of 6 percent below their 1990 levels from 2008 to 2012.

However, between 1990 and 2008, Canada's GHG emissions increased by around 24.1 percent, making it unlikely to meet that target.

In 2009, Canada signed the non-binding Copenhagen Accord and agreed to reduce its GHG emissions by 17 percent from its 2005 levels by 2020.

In a surprising blow to the international efforts to curb emissions, Canada announced withdrawal from the Kyoto Protocol on Dec. 12, 2011, one day after negotiators from nearly 200 countries and regions met in Durban, South Africa for the climate talks.

Canada's withdrawal has drawn widespread international criticism. However, Kent claimed that Canada, the only country to repudiate the Kyoto Accord, needed to avoid 14 billion U.S. dollars in penalties for not meeting its Kyoto targets. Endi